1. Field of the Invention
The present invention relates generally to scanners and scanning methods, and more particularly to a duplexing printer and scanner auto-document feeder module.
2. Description of the Related Art
All-in-one machines typically perform functions such as printing, scanning, copying, and faxing in either a stand alone fashion or in conjunction with a personal computer and define a growing market for peripheral devices. These devices eliminate clutter in a business or home office by combining the desirable functionality of various machines into a single unit, while maintaining an affordable cost. Various all-in-one machines currently in the marketplace use thermal inkjet technology as a means for printing received fax documents, original documents, and copied or scanned images or text. Thermal inkjet printing devices utilize consumable inkjet cartridges in fluid communication with a printhead to record text and images on a print media. The printhead typically moves on a carriage relative to the media path and a control system activates the printhead to selectively eject ink droplets onto the print media.
Scanners are used to scan a target image and create scanned image data which can be displayed on a computer monitor, which can be used by a computer program, which can be printed, which can be faxed, etc. Scanned data may be saved to memory or a magnetic or optical drive, or other fixed or removable memory device. Scanning devices may be packaged in a stand-alone housing or as part of the all-in-one device, as described herein, including a printing module to perform scanning as well as standard copying functions.
Scanners typically include a housing aperture defined by an edge wherein a platen is located. A target document is positioned on the platen for scanning of the text or image by a scanbar. Depending on the positioning of the scanbar relative to the platen, the platen may be transparent where the scanbar is beneath the platen or may be solid where the scanbar is above the platen. For a typical flatbed scanner, the scanbar will be below the platen, which will have a transparent section to allow for the scan operation.
The scanner may also include an auto-document feeder (ADF) to automatically and sequentially feed a plurality of documents to a scan module. The automatic document feeder typically comprises a feed tray and an input device which feeds a single sheet from the stack of media on the feed tray into the automatic document feeder media path. The single sheet of media passes a reading position where the media is illuminated and image data is created by the scanbar representing images on the media. The media then passes from the auto-document feeder to a stacking tray where the media remains until all of the media from the feed tray has been scanned and is removed from the stacking tray at the output side of the auto-document feeder.
Generally, most auto-document feeders are single-side or simplex media feeding devices. However, many end-users desire the ability to perform double-sided or duplex operations. To perform a duplex scan, the media must be turned which may be performed manually by the user. Alternatively, prior art patents have taught various mechanical means for reversing media sides and performing double-sided or duplex scanning. According to one method of duplex scanning the auto-document feeder comprises first and second image sensors to scan first and second sides of the media, respectively. However, the problem with these devices is that the two image sensors require large amounts of space and therefore make the equipment footprint much larger. This is not suitable for many applications, especially home-office equipment or small office equipment and further increases the costs of the device which is also undesirable.
Another problem with auto-document feeding scanners is that the auto-document feed portion is typically located on the upper portion of the device. Due to the large size of the image sensing equipment, or dual units for duplexing as previously described, the duplexing auto-document feeders extend from the upper portion of the office peripheral and have an obtrusive design architecture. In particular, the auto-document feeders typically add to the overall height of the machine which is undesirable. Further, such architecture results in difficulty incorporating an overall machine appearance scheme.
In addition to the previously indicated problems, one of ordinary skill in the art will recognize that the prior art descriptions herein require separate document handling systems for the auto-document feeding scanner and a printer component. This is disadvantageous because multiple parts are required to perform the same function of document handling. This also leads to added expense for the all-in-one device.
Given the foregoing deficiencies, it will be appreciated that an improved apparatus for scanning is needed which utilizes a modular duplexer to convert a simplex printer to a duplex scanner and duplex printer and which further has a smaller footprint with lower height requirements than state of the art duplexing auto-document feeding units.